intl/textdomain.c

   1 /* Implementation of the textdomain(3) function.
   2    Copyright (C) 1995, 1996, 1997, 1998, 2000 Free Software Foundation, Inc.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #ifdef HAVE_CONFIG_H
  20 # include <config.h>
  21 #endif
  22
  23 #if defined STDC_HEADERS || defined _LIBC
  24 # include <stdlib.h>
  25 #endif
  26
  27 #if defined STDC_HEADERS || defined HAVE_STRING_H || defined _LIBC
  28 # include <string.h>
  29 #else
  30 # include <strings.h>
  31 # ifndef memcpy
  32 #  define memcpy(Dst, Src, Num) bcopy (Src, Dst, Num)
  33 # endif
  34 #endif
  35
  36 #ifdef _LIBC
  37 # include <libintl.h>
  38 #else
  39 # include "libgettext.h"
  40 #endif
  41 #include "gettext.h"
  42 #include "gettextP.h"
  43
  44 #ifdef _LIBC
  45 /* We have to handle multi-threaded applications.  */
  46 # include <bits/libc-lock.h>
  47 #else
  48 /* Provide dummy implementation if this is outside glibc.  */
  49 # define __libc_rwlock_define(CLASS, NAME)
  50 # define __libc_rwlock_wrlock(NAME)
  51 # define __libc_rwlock_unlock(NAME)
  52 #endif
  53
  54 /* @@ end of prolog @@ */
  55
  56 /* Name of the default text domain.  */
  57 extern const char _nl_default_default_domain[];
  58
  59 /* Default text domain in which entries for gettext(3) are to be found.  */
  60 extern const char *_nl_current_default_domain;
  61
  62
  63 /* Names for the libintl functions are a problem.  They must not clash
  64    with existing names and they should follow ANSI C.  But this source
  65    code is also used in GNU C Library where the names have a __
  66    prefix.  So we have to make a difference here.  */
  67 #ifdef _LIBC
  68 # define TEXTDOMAIN __textdomain
  69 # ifndef strdup
  70 #  define strdup(str) __strdup (str)
  71 # endif
  72 #else
  73 # define TEXTDOMAIN textdomain__
  74 #endif
  75
  76 /* Lock variable to protect the global data in the gettext implementation.  */
  77 __libc_rwlock_define (extern, _nl_state_lock)
  78
  79 /* Set the current default message catalog to DOMAINNAME.
  80    If DOMAINNAME is null, return the current default.
  81    If DOMAINNAME is "", reset to the default of "messages".  */
  82 char *
  83 TEXTDOMAIN (domainname)
  84      const char *domainname;
  85 {
  86   char *new_domain;
  87   char *old_domain;
  88
  89   /* A NULL pointer requests the current setting.  */
  90   if (domainname == NULL)
  91     return (char *) _nl_current_default_domain;
  92
  93   __libc_rwlock_wrlock (_nl_state_lock);
  94
  95   old_domain = (char *) _nl_current_default_domain;
  96
  97   /* If domain name is the null string set to default domain "messages".  */
  98   if (domainname[0] == '\0'
  99       || strcmp (domainname, _nl_default_default_domain) == 0)
 100     {
 101       _nl_current_default_domain = _nl_default_default_domain;
 102       new_domain = (char *) _nl_current_default_domain;
 103     }
 104   else if (strcmp (domainname, old_domain) == 0)
 105     /* This can happen and people will use it to signal that some
 106        environment variable changed.  */
 107     new_domain = old_domain;
 108   else
 109     {
 110       /* If the following malloc fails `_nl_current_default_domain'
 111          will be NULL.  This value will be returned and so signals we
 112          are out of core.  */
 113 #if defined _LIBC || defined HAVE_STRDUP
 114       new_domain = strdup (domainname);
 115 #else
 116       size_t len = strlen (domainname) + 1;
 117       new_domain = (char *) malloc (len);
 118       if (new_domain != NULL)
 119         memcpy (new_domain, domainname, len);
 120 #endif
 121
 122       if (new_domain != NULL)
 123         _nl_current_default_domain = new_domain;
 124     }
 125
 126   /* We use this possibility to signal a change of the loaded catalogs
 127      since this is most likely the case and there is no other easy we
 128      to do it.  Do it only when the call was successful.  */
 129   if (new_domain != NULL)
 130     {
 131       ++_nl_msg_cat_cntr;
 132
 133       if (old_domain != new_domain && old_domain != _nl_default_default_domain)
 134         free (old_domain);
 135     }
 136
 137   __libc_rwlock_unlock (_nl_state_lock);
 138
 139   return new_domain;
 140 }
 141
 142 #ifdef _LIBC
 143 /* Alias for function name in GNU C Library.  */
 144 weak_alias (__textdomain, textdomain);
 145 #endif